Traversing mechanism for mortars



June 10, 1952 D. M. LONTZ 2,599,555

TRAVERSING MECHANISM FOR MORTARS 5 Sheets-Sheet 1 Filed June 7, 1946 W U v .97 DUJIJLEYM.LDNTZ1 June 10, 1952 D. M. LONTZ TRAVERSING MECHANISM FOR MORTARS 5 Sheets-Sheet 2 Filed June 7, 1946 DUDLEY ML :1 M2,

3% 12! djfiagw Wag a June 1952 D. M. LONTZ 2,599,565

TRAVERSING MECHANISM FOR MORTARS Filed June '7, 1946 5 Sheets-Sheet 3 amen KOO DUDLEYM.L EJNT'Z June 10, 1952 D. M. LONTZ 2,599,565

" TRAVERSING MECHANISM FOR MORTARS Filed June 7, 1946 5 Sheets-Sheet 4 liiiii 5111mm '5' a I UDLEYM.LE1NT z June 10, 1952 D. M. LONTZ TRAVERSING MECHANISM FOR MORTARS 5 Sheets-Sheet 5 Filed June 7, 1946 L T N U M Y E L D u D Patented June 10, 1952 UNITED STATES PATENT OFFICE (Granted under the act of March 3, 1883, as amended April 30, 1928; 370 O. G. 757) 6 Claims.

The invention described herein may be manufactured and used by or for the Government for governmental purposes, without the payment to me of any royalty thereon.

This invention relates to mechanism for traversing artillery pieces, particularly those of relatively large size. While the invention is not limited to any particular size, it is herein described as applied to a mobile 10" mortar. Mortars of this size are of great weight so that it is difiicult to manipulate them without power-driven mechanism. Since, however, power is ordinarily not obtainable for a mobile piece, it is desirable to provide for mortars of this size suitable traversing mechanism which can be manually actuated.

In modern warfare, speed of operation as well as accuracy is of great importance. It is, therefore, desirable that guns and mortars of large calibers be mounted in such a manner that they can be quickly transported from one location to another with the least possible delay in changing from firing position to traveling position and from traveling position to firing position. It is also important that mortars be capable of fine traversing adjustment, since the modern mortar is capable of remarkably accurate fire if subject to proper control. Furthermore, it is highly desirable that mortars be capable of rapid traversing through wide angles so that shifts to different targets can easily and quickly be made.

It is an object of the present invention to provide means by which a mortar of large caliber can be quickly and accurately traversed through a wide are which can be 360 if desired, but can also be accurately traversed through small angles. It should be understood that although the use of the traversing mechanism of this invention is here described in connection with artillery carriages, the method by which the traversing mechanism operates is also readily adaptable to other applications such as in machine tools, for one. Various advantageous features of the invention will be apparent from the following description of an embodiment thereof and from the drawings of which:

Fig. 1 is a side elevational view of a mortar embodying this invention and shown in the firing position;

Fig. 2 is an elevational view of one of the jack support members;

Fig. 3 is a view showing how the ball or the ball and socket joint is keyed to the mortar car riage;

Fig. 4 is a top elevational view of the track elements;

Fig. 5 is an enlarged sectional view taken on the plane 5--5 of Fig. 4;

Fig. 6 is a partial front elevational view of the axle and associated elements in the collapsed or stowed position for transporting;

Fig. 7 is a sectional view of the socket mount for the mortar;

Fig. 8 is an enlarged scale elevational view of the rail clamp element;

Fig. 9 is a multi-plane sectional view oi Fig. 8 taken along the line 9-9 thereof;

Fig. 10 is a partial sectional view of Fig. 8 taken along the plane Ill-ll) thereof;

Fig. 11 is a schematic side elevational view of the traversing mechanism;

Fig. 12' is a side elevational view, partly in section, of the adjustable link element;

Fig. 13 is a top elevational view of the rail clamp;

Fig. 14 is a top elevational View of the base plate, carriage, track and trail;

Fig. 15 is a view partly in section showing the method used for transmitting rotational power to the universal joint shaft;

Fig. 16 is a side elevational view partly in section of the universal joint; and

Fig. 17 is a detail view of the universal joint showing the operating slot.

The drawings illustrate a mortar of large caliber comprising essentially a tube or barrel 20 and a recoil mechanism 22 mounted on a carriage generally indicated at 24. The carriage is supported for transportation by a pair of rubbertired wheels connected by an axle 32 to which is attached a trail 34. Connected to the carriage by a ball and socket joint 35 is a base plate 38 which rests upon the ground and is designed to take the recoil stresses when the mortar is fired. The ball and socket joint 36 is in line with the axis of the barrel 20 so that it receives nearly all of the recoil thrust and transmits it to the base plate 38.

Suitable mechanism is provided for elevating the mortar barrel when in firing position, such mechanism being well known and not herein described in detail. The present invention has to do with an improved traversing mechanism for such large portable ordnance. For this purpose an arcuate track 40 is laid beneath the carriage concentrically with joint 36. This track is preferably furnished in sections of suitable size which may be secured together by bolts or pins to form an arcuate track of any desired length of are up to a complete circle. For ordinary purposes a track extending through an arc of approximately 120 will usually be sufficient. In case a change of target necessitates a larger traverse, sections of track can be disconnected from one end of the entire track and connected to the other end.

The track 40, as shown, is preferably a T-rail 4| with an integrally formed, channel-shaped base 42 adapted to rest upon the ground. Suitable links 50 connect the track with extensions 5| of the base plate 38 so as to maintain the arc of track 40 concentric with the ball and socket joint 36.

A pair of built-in jacks 52 are provided to elevate the entire carriage sufliciently to lift the wheels 30 clear of track 40 and also to'provide means for any desired cross-leveling. Each jack is pivotally connected at 54 to a bracket 56 which is swivelly mounted on the axle. 32 so that the jack can be swung from a horizontal traveling position alongside of the axle down to a vertical working position in which it serves to support the mortar carriage in conjunction with the other jack and the joint 36. A clamp 51 is provided on axle 32 to hold each jack in traveling position when not in use. In order to maintain the jacks 52 in a vertical position when in use, each is provided with'a fin or lug 58 which engages between a pair of parallel ears 60 projecting from axle 32. At the lower end ofv each jack is a flanged wheel 64 in radial alignment with the center of the ball and socket joint 36 so that the wheel is adapted to ride on track 40. The jack is extensible, any suitable means being employed for this purpose. As shown, the wheel 64 is mounted in the bifurcated end 65 of a threaded shaft 66 and shaft 66 is in threaded engagement with a nut 68 mounted within the housing 69 of the jack 52. The nut is held by suitable means against axial movement relative to the housing 69. When the nut is rotated, the threaded shaft is drawn into or thrust from the housing 69 according to the direction of the rotation, thus shortening or lengthening the jack in a manner well known in the art. For the rotation of the. nut 68. a short shaft is provided with gear teethII meshing with teeth, I2 on the periphery of the nut, the shaft 10 being rotatable by a crank I4 connected thereto through bevel gears 16 and 18, or-by a wrench (not shown) engaging on a projecting'squared end portion 80 of the shaft. The crank- I4 is intended for rapid-operation of the jack up to the point where substantial resistance is encountered. At this point a long-handled wrench is preferably employed for actuating the jack to lift the mortar and carriage until the wheels are clear of the rail. In the event track is laid on uneven terrain, one ofjacks 52 can be further actuated the amount necessary to tilt axle 32 sufliciently to effect cross-leveling of carriage 24. A bellows sleeve 82 ispreferably provided to surround the portion of the threaded shaft 66 which projects from the housing 69 so'as to protect the shaft from dirt andmoisture and to prevent loss of lubrication therefrom.

The ball and socket joint 36 is made with a swivel construction so as to permit traversing movement of the mortar through any desired angle of azimuth and also to permit depression of the mortar barrel from a high angle of approximately 80 to an angle of about from the horizontal. The socket is contained in a cylindrical wall 84 (Fig. '7) which is secured to or is integral with the baseplate 38'. The socket itself consists of acylindrical base 86 which is suitably secured to the base plate 38 and a rotatable portion consisting of a collar 88 and a suitable cap 90. An outwardly projecting flange 92 on the cylindrical base 86 inter-engages with an internal groove 94 in the collar 88 to retain the rotatable collar within the wall 84. For assembling purposes the collar 88 is made in two separate halves which are assembled with the base 86 prior to insertion within the wall 84. After insertion, the base is bolted to the floor of the base plate 38. The socket is then ready to receive the ball portion of joint 36 after which the cap is bolted to the collar 88. When thus assembled, the cap 90 and collar 88 rotate as a unit about an axis perpendicular to the base plate 38 when the mortar is traversed.

A member I02 serves as a link between base plate 38 and carriage 24. Such member shown in Fig. 3 comprises a body portion I06 provided with integral keys I09 on either side thereof and a centrally located U-shaped slot II9 therein. Parallel oppositely disposed arms I 04 and I04 terminating in spherically curved sections 95 and 96 respectively are integrally formedwith body portion I06. Barrel 20 is provided with an integral neck portion I08 terminating in a spherically shaped end 91 arranged to be assembled between sections 95 and 96 to'form a ball I00. In this position, neck portion I08'ex' tends between arms I04 and I04 and falls within U-shaped slot H9. Sections 95, 96, and 91 are suitably apertured to receive a pin 93 preferably having convexly curved ends which will complete the spherical periphery of ball I 00. Member I02 is in turn secured to a yoke I2-I by means of keys I09. The ends of yoke I2I are suitably connected to the sides of carriage 24. a

The ball and socket joint 36' thus permits a certain amount of lateral tilting or leveling of the mortar and carriage with respect tothe base plate 38. For such adjustments the ball I00 moves as a unit in the socket. When the mortar barrel is being elevated or depressed, the central section 91 is the only portion of ball I00 that moves, rotating in a vertical plane on pin 98 with neck I08 riding between the arms of the cap 90. When the mortar is traversed the cap 90 and collar 88'rota'te with the mortar and ball since they are free to turn as aunit on cylindrical base 86/ V V In preparing the mortar for travel the'barrel 20 is depressed to an angle of abo'ut- 25 with the base plate 38 prior to rocking itand the base plate together about the axle 32 to aposition in which it can be secured to the trail 34-. To permit this degree of depressionof the barrel, the wall 84 is made with a gap; adapted toreceive the neck I08: when the barrel' is in line with the long axis of the baseplate" 38; For this purpose also the collar 88 is: notched as shown at I29- inFig. 7', this notch being'always in line with the barrel since the -collar turns with the mortar-when the latter is traversed.

When the mortar is brought to a location; in which it is to be setup for action, the segments of track 40 are laid on the ground and fastened to each other and to the base plate 38, the track being arranged so that its mid point is=approximately in line with the socket-joint 36 and} the direction of the target; Tworampslnot shown) located relative to track 40 by means-of dowels are placed upon the track assembly. These ramps areprovided with pockets conforming approximately to the rubber-tired wheels SU onth'' aceacsozs gun carriage 24. The gun carriage is then rolled up the ramps until wheels 30 are located in the aforesaid pockets. The entire mortar carriage is then permitted to tilt rearwardly until base plate 38 seats upon the ground. After thi has been done, it will be found that extensions 5| can be attached between base plate 38 and track assembly 40 with little difficulty since a screw adjustment (not shown) is provided for lengthening or shortening link extensions 5|. It may be pointed out at this time that since jacks 52 can pivot about pins 54, it is not absolutely essential that track 40 coincide with a circle described from the center of the socket in joint 35.

After these operations have been performed, the two jack assemblies 52 are released from their carrying clamps 51 and placed in a vertical position with flanged wheels 64 on rail 4|. Jacks 52 are then operated to lift wheels 30 until they clear the ramps, whereupon the ramps may be removed to one side. By pushing on the outer end of trail 34, the mortar can be traversed to a position wherein the barrel 20 is pointing in a direction which is the approximate bearing of the target. Adjustable link assembly H4 is then released from its traveling clamp I32 and clamp H (Fig. 8) is secured to rail 4| thereby putting the traversing mechanism in readiness for the firing of the mortar.

A detent IN is vertically mounted in clamp body H0 and is biased downwardly by a spring I03. The head I of detent I0| is shaped to en gage in any selected one of a plurality of spaced notches 39 provided in the outer periphery of track rail 4|. Detent IOI projects upwardly out of clamp body H0 and may be withdrawn from a notch 39 in track 40 by the action of a bellcrank 43 pivotally mounted on a pin 45 in clamp body H0. Bell-crank 43 is in turn actuated by a push-pull rod 49 which is provided with a means of adjustment as a link shown at 41. Push-pull rod 49 is threadably engaged by link 41 and is suitably supported in a bracket I01 formed on clamp body I I0.

To rigidly secure clamp body IIO to the track 40 at any position selected by detent IN, a pair of clamp jaws III are provided. Suitable bolts H2 may be provided to pass through clamp jaws III and cooperate with threaded holes H3 in clamp body I I0. A nut H5 is threadably secured to the other end of bolt I I2 to draw together the two portions of the clamp into tight frictional engagement with the sides of rail 4|. The clamp body H0 is connected to the carriage through link assembly H4 whose length can be adjustably varied to serve as a slow motion traversing mechanism for precise aiming. This link assembly H4, as shown in Fig. 12, comprises a cylindrical housing H6, one end of which is provided with a fitting H8 arranged to be pivotally attached to a horizontally swiveled portion |2| of the clamp body H0 by pin I25. Secured to the other end of the housing H6 is a nut I having in threaded engagement therewith a threaded shaft I22. Thi threaded shaft projects into the interior of the housing H6 and may be provided with an end collar I24 to guide the inner end as it travels up and down within the housing I I6, thus avoiding skew stresses on the screw threads. The upper end of the shaft I22 is secured in a universal joint assembly I26 by which the shaft is connected through a series of shaft segment gears and universal joints indicated generally by H! to a suitable handwheel I30 by operation of which the shaft I22 may be rotated in either direction. Universal joint assembly I26 comprises a ball portion I33 on the end of shaft I22 being provided with opposing slots I34 to cooperate with a pair of rollers I35 mounted in a universal joint housing I36, such housing being axially secured to a shaft I31 which is rotatably secured to universal joints III. When shaft I31 is rotated by handwheel I30, rollers I35 in turn rotate shaft I22. A bellows sleeve I23 i preferably provided between universal joint I26 and nut I20 to surround the exposed portion of shaft I22. In this manner, the mortar can be traversed accurately through small angles of azimuth to insure accuracy of direction in firing.

The universal joint I26 is in the nature of a ball and socket joint, permitting the link assembly I I4 with the clamp body H0 to be swung up to a position approximately parallel to the axle 32, in which position the link assembly II 4 is secured, when not in use, by a clamp I32 on the axle.

An embodiment of the invention having thus been described, it is to be understood that the invention is not intended to be limited to the exact details of such embodiment but may include such modification and changes as come within the scope of the appended claims.

I claim:

1. In combination, a gun having a barrel, a carriage pivotally mounted about a transverse axle and arranged to support said gun, a pair of wheels mounted on said axle, a mobile trail fixedly secured at one end to said axle and extending forwardly thereof to support the barrel end of said gun for transportation, a base plate arranged to rest on the ground rearwardly of said carriage when said gun is placed in firin position, said base plate having a rotatable socket joint therein, a ball member fixedly secured to said carriage and extending rearwardly therefrom to seat in said socket joint and serve as a pivot for the traverse movement of said carriage, an arcuate track laid concentric with said ball and socket joint, adjustable link means for connecting said track withsaid base plate, a pair of extensible jacks operative on said carriage axle to raise said wheels thereon off the ground, roller means on the free end of each of said jacks cooperating with said track to permit traverse of said raised carriage about said ball and socket joint as a center, and means for stowing said jacks parallel to said axle when said gun and said carriage are arranged for transportation.

2. In combination with a mobile artillery carriage mounted on an axle and rotatable about a base plate as a center, an arcuate track laid concentric with the base plate, a swivel mounted adjacent either end of the axle, a screw-threaded jack pivotally secured to each of said swivels and arranged for movement between a stowed position parallel to the longitudinal axis of the axle and an operative position in a plane normal to said stowed position, roller means on the free end of each of said jacks engageable in the operative position thereof with said track, means on the axle engageable with said jacks for retaining the latter in their operative position, and means for manually extending said jacks to lift the axle and thereby the carriage off the ground to permit traversing movement thereof along said arcuate track, each of said jacks being individually actuable to cross-level the carriage relative to the ground on which said track is laid.

3. In combination with a gun having a barrel, a carriage pivotally mounted about a transverse axle and arranged to support the gun, avail ofwheels mounted on saidaxle, a baseplate are ranged to rest on the ground rearwardly of said carriage when said gun-is placed in firing position, said base plate having a rotatable socket joint therein, a ball member seated in said socket and comprisin the free ends of a pair of arms secured to said carriage and the free end of an in-- termediate member secured to the rear end of said gun barrel, said intermediate member being pivoted relative to said fixed armswhereby said barrel is arranged for movement in a vertical plane, a cap fitted to said socket, over said ,ball member and provided with a passage for saidintermediate member whereby traverse" of said 'c'arriage rotates said socket without interfering with the elevation and depression of said gun barrel relative to said carriage, an arcuate track: laid concentric with said ball and socket joint, 9. pair of extensible jacks for raising said carriage off the ground, and roller means on the free ends" of said jacks cooperating with said track to permit traverse of said carriage and said gun'about said ball and socket joint as a center.

4. In a mobile artillery piece; the combination of a mobile carriage, a base plate disposed rearwardly of said carriage, a ball and socket joint connecting said base plate with said carriage, an arcuate track concentric with said ball and socket joint, a pair of extensible jacks for raising said carriage off the ground, roller means on-the free ends of said jacks cooperating with said track to permit traverse movement of said raised carriage about said ball and socket joint as a center,- an adjustable member clamped at one end to said track between said jacks and fixedly secured: at the other end thereof to said-carriage, andmeans for adjusting the length of said-member to move said carriage toward or away from the point of clamping on said track whereby fine traverse of the artillery piece effected. U

5. In combination with an artillery piece, a mobilecarriag'e mounted on an-axle and arranged to support said artillery piece, a base plate arranged to rest on the ground rearwardly or said carriage when said gun is placed in firingposition, said base plate having arotatable socket joint therein, a ball member fixedly secured to said carriage and extending rearwardly therefrom to seat in said socket joint and serve as a pivot for the traverse movement of said carriage, an arcuate track laid concentric with said ball and socket, a. pair of extensible jacks engageable with said track and operable on said axle to raise said carriage off the ground, an adjustable member having one end rotatably mounted adjacent one end of said axle for movement between a stowed and an extended position, clamp means secured to said track between said jacks, means for pivotally' and swivelly securing the other end of said adjustable member in said extended position to said clamp means, and means for adjusting the length of said member to move said carriage along said track toward or away from said clamp means whereby fine traverse of the artillery piece is effected. 6. The combination defined in claim 5 wherein said track is provided with a rail having aplurality of notches therein, and wherein said clamp means is provided with adetent selectively enga fiable in any of said notches for positioning said carriage so that said artillery piece is substantially in line with the direction of a selected target. I

DUDLEY M. LONTZ.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number 7 Name Date 150,024 Goddard Apr. 21, 187?: 424,496 Nordenfelt Apr. 1, 1890 1,145,070 Heileman et a1. July 13, 1915 1,163,036 Rabba Dec. 7, 1915 1,173,215 Rausenberger Feb. 29, 1916 1,310,888 Schneider July 22, 1919 1,665,176 Rimailho Apr. 3, 1928 2,194,849 Denoix Mar, 26, 1940 2,208,015 Caulkins July 16, 1940 FOREIGN PATENTS Number Country Date, 7

300,702 Germany Mar. 2, 1917 

